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37 lines
1.3 KiB
C
37 lines
1.3 KiB
C
/* strlen -- determine the length of a string.
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For Intel 80x86, x>=3.
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Copyright (C) 1991, 1992, 1993 Free Software Foundation, Inc.
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Contributed by Torbjorn Granlund (tege@sics.se).
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If
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not, write to the Free Software Foundation, Inc., 675 Mass Ave,
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Cambridge, MA 02139, USA. */
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#include <ansidecl.h>
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#include <string.h>
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size_t
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DEFUN(strlen, (str), CONST char *str)
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{
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int cnt;
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asm("cld\n" /* Search forward. */
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/* Some old versions of gas need `repne' instead of `repnz'. */
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"repnz\n" /* Look for a zero byte. */
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"scasb" /* %0, %1, %3 */ :
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"=c" (cnt) : "D" (str), "0" (-1), "a" (0));
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return -2 - cnt;
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}
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